adding basic arithmetic functions 
adding basic arithmetic functions 


hoangt/goblin-core,tangyibin/goblin-core,tangyibin/goblin-core,hoangt/goblin-core,tangyibin/goblin-core,tangyibin/goblin-core,hoangt/goblin-core,hoangt/goblin-core,tangyibin/goblin-core,tangyibin/goblin-core,tangyibin/goblin-core,tangyibin/goblin-core,hoangt/goblin-core,hoangt/goblin-core,hoangt/goblin-core,hoangt/goblin-core,hoangt/goblin-core,hoangt/goblin-core,hoangt/goblin-core,tangyibin/goblin-core,tangyibin/goblin-core,tangyibin/goblin-core